In the beginning there was the command line. A keyboard input to a type on paper output. Then UNIX. The first editor was 'ed' (edit). It was line based, designed for a keyboard onto paper output. It was enhanced to become 'ex'.<p>When the happy hackers at UC Berkeley were porting UNIX onto VAXen (becoming BSD Unix), CRT terminals were available, notably the DEC VT-100 and other less expensive ones. These terminals had commands that would move the terminal cursor around the screen, allowing a editing program to modify the 24 (or 25) lines of 80 characters on the display. But the terminal commands were DIFFERENT. So the configuration file TERMCAP and the C library libcurses were created.<p>Then 'ed' / 'ex' was expanded to become 'vi' (visual, not six). Note that the 'ed'/'ex' commands are still there, invoked by the ':' command. Now there was a full screen text editor that worked on different CRT terminals.<p>This was all before UX design existed. It evolved. 'vi' was a giant leap up from a typewriter editor.<p>(We don't need no stinkin' mices)